GUIDE How to Enable AMD RX 6800, RX 6800XT and RX 6900XT on macOS Big Sur and Later

[Nixgehtmehr]

It's then either your NVMe or the PSU for sure. It could be the CPU and memory too. But start diagnosing the system from NVMe, then PSU, then the CPU and lastly the memory.

NVMe ist a WD 850 1Tb - but it is the model with heasink which comes for the PS5
PSU 750W Dark Power BeQuit - very solid
CPU 10900kf without iGPU
Memory Crucial 2x 32Gb Modules DDR4 3200

 

[EliteMacx86]

NVMe ist a WD 850 1Tb - but it is the model with heasink which comes for the PS5
PSU 750W Dark Power BeQuit - very solid
CPU 10900kf without iGPU
Memory Crucial 2x 32Gb Modules DDR4 3200

We had exactly the same scenario but the CPU turns out to be faulty. Once replaced, everything was good.

 

[Nixgehtmehr]

We had exactly the same scenario but the CPU turns out to be faulty. Once replaced, everything was good.

Thats worse case scenario - because I have no spare CPU. How can a CPU be defect? Never had this - CPU runs very well in Windows and Unraid with VMs. Are you shure that the CPU can be the reason. How about to reduce Clockspeed via Bios to make it more stable.

Maybe CPU doesnt work well with iMac Pro because its a Bios for Xenon Cpus?

 

[EliteMacx86]

Thats worse case scenario - because I have no spare CPU. How can a CPU be defect? Never had this - CPU runs very well in Windows and Unraid with VMs.

As mentioned above, the first thing to diagnose is the NVMe, then the PSU, then the memory and lastly the CPU. In our case, our CPU was 12900K which worked for a few weeks and another worked for a year or so. Probably, it was from bad batch. You never know the technology, we had cases like DOA. So, it just happens.

Are you shure that the CPU can be the reason.

Until you diagnose the system, no one can know. It could be one of the components. It could be also possible that the GPU you're using is faulty itself. Recently a member of this forum had a case of WiFi on a real Mac, turned out his WiFi/BT Card was faulty. If you don't have spare components, take the system to any local computer shop.

How about to reduce Clockspeed via Bios to make it more stable

We have seen CPUs dying in real environments during tests, so reducing the clock speed or undervolting, will not help. There could be also a chance that your Motherboard could be faulty. You never know until you start diagnosing.

 

[EliteMacx86]

Maybe CPU doesnt work well with iMac Pro because its a Bios for Xenon Cpus?

It has nothing to do. If you still think so, feel free to change the SMBIOS.

 

[ilyalazutkin]

Hi, there codecs working with RX 6800?

 

[EliteMacx86]

Hi, there codecs working with RX 6800?

Which Codec?

 

[ilyalazutkin]

I have RX 6800, Installed Big Sur, all good with pikera, but VDA decoder not working, i guess card not initialised with full power / acceleration.

Could be some problems with
113-D414-R68GOL rom version (Gigabyte RX 6800 Gaming OC) ?

I will be glad if you help

 

[EliteMacx86]

I have RX 6800, Installed Big Sur, all good with pikera, but VDA decoder not working, i guess card not initialised with full power / acceleration.

Could be some problems with
113-D414-R68GOL rom version (Gigabyte RX 6800 Gaming OC) ?

I will be glad if you help

Use iMacPro1,1 and you should be good to go!

 

[ilyalazutkin]

or MacPro 7,1 ? )
Ive tryed both, but all usb ports disappears. Made kext with USBToolBox/tool generated kext from Win - and no luck. Mac Pro 6,1 with UsbInjectAll - works perfect (except video card)